I won't repeat what others have said - so I assume you read everything
before reading this.
It all depends on several factors - first of all, "Gold" as such is a
simulated color that is not part of the color depth that computers use.
Such simulation can provide different results - a particular shade of Gold
looks better on a red background or not - something else probably looks
better on a blue background.
If you don't want to use this for text - and just for AutoShape fills, try
using a gradient rather than a solid fill - this will look more realistic.
You can also simulate Gold by using a Gold texture fill.
Sometimes, you can just create something in Photoshop or Paint Shop Pro -
and then get that inside PowerPoint.